Axial Cylinder Research Articles

Dynamic modeling and vibration characteristics analysis of cylinder with local defects in axial piston pump

The piston/cylinder pair suffers from excessive wear during the operation of axial piston pumps, and the local defects usually occur in the brass bush in the cylinder bore. Generally, the wear of cylinder is the main source of failure that affects the reliability of axial piston pumps. Thus, it is necessary to conduct an in-depth study on the vibration generated by the cylinder with local defects. Considering the effect of defect dimension, a novel time-varying displacement excitation model of the axial piston pump cylinder defect is proposed and establishes a 13 degrees of freedom lumped parameter dynamic model for cylinder fault. Then, investigating the effects of length and depth of the defect on the spectral amplitude and exploring the fault characteristic frequency of cylinder. Lastly, the model was validated on a test rig. The results demonstrate that the constructed model can predict the vibration caused by a locally defective cylinder with a frequency domain error of 0.69% and the fault characteristic frequency of cylinder is the same as its rotational frequency. Moreover, the defect length will influence the amplitude and duration of the cylinder-defect pulse waveform. The fault excitation amplitudes increase with the increase of defect depths.

Shaking a container full of perfect liquid; a tractable case, a torus shell, exhibits a virtual wall

Manipulation (‘shaking’) of a rigid container filled with incompressible liquid starting from stationary generally results in some displacement, or mixing, of the liquid within it. If the liquid also has zero viscosity, a ‘perfect’ or ‘Euler’ liquid, Kelvin’s theorems dramatically simplify the flow analysis. Response is instantaneous; stop the container and all liquid motion stops. In fact an arbitrary manipulation can be considered as alternating infinitesimal translations and rotations of the container. Relative to the container, the liquid is stationary during every translation. Infinitesimal rotations (an infinitesimal vector along the rotation axis) resolve into three orthogonal components in the container frame. Each generates its own infinitesimal liquid displacement vector field. Their combined consequences are usually obscure. Rather than a volume flow, a surface flow in 3D is considerably easier, the liquid slipping freely in a shell, sandwiched between two nested closed surfaces with constant infinitesimal gap. The closedness avoids extra boundaries. The two dimensionality admits a scalar streamfunction determined by the container angular velocity vector. Manipulation of the container angular velocity at will, usually leads to an infinitely rich variety of area preserving re-configurations of the liquid. In particular, any chosen point of the liquid can be moved, in the shell container frame, to any other chosen point. However, for a torus (shell) with a small enough hole (diameter < 0.195 torus diameter), there exists a virtual wall, a hypothetical axial cylinder intersecting the torus. No matter how the torus is manipulated, liquid inside the cylinder stays inside; outside stays outside. The analysis, solving for the streamfunction, is based on the relative vorticity, and the conformal mapping of a torus to a (periodic) rectangle, which lead to a fairly simple convolution integral formula for the flow.

Method for determining eigen numbers in heat conduction problems for a cylinder

RELEVANCE. Due to the difficulties of finding eigenvalues and proper functions for bodies with axial (cylinder) and central (ball) symmetries defined in classical methods from the edge Sturm-Liouville problems, including Bessel equations whose exact analytical solutions are not obtained (known only numerical solutions, described by approximation formulas), there is a need to develop analytical methods of their solution.THE PURPOSE. Using orthogonal methods of weighted residuals, an approximate analytical method for determining eigenfunctions and eigenvalues in boundary value problems with axial and central symmetry (cylinder, ball) has been developed.METHODS. The method is based on the use of orthogonal systems of coordinate functions and additional boundary conditions. Latter are in such a form that their fulfillment by the desired solution is equivalent to the fulfillment of the differential equation of the boundary value problem at the boundary points of the region, leading to its fulfillment inside the considered region. Moreover, the accuracy of the equation depends on the number of approximations, which, in turn, depends on the number of additional boundary conditions used. Using the orthogonality property of trigonometric coordinate functions included in a series representing eigenfunctions makes it possible to increase the accuracy of the fulfillment of the differential equation of the Sturm-Liouville boundary value problem and the accuracy of determining the eigenvalues. To satisfy the initial condition, its residual is compiled and the condition of its orthogonality to all coordinate functions is required. The orthogonality of trigonometric systems of coordinate functions with respect to the unknown constants of integration leads to a system of algebraic linear equations, the number of which is equal to the number of approximations. As a result, the fulfillment of the initial condition is simplified and the accuracy of its fulfillment is increased.RESULTS. The advantage of the method is that the resulting solution contains only simple algebraic expressions, excluding special functions (Bessel function, Legendre function, gamma function).CONCLUSION. Thus, bypassing direct integration over a spatial variable, the use of additional boundary conditions makes it possible to find a solution of any complexity of the equations of the Sturm-Liouville boundary value problem, which reduces to the definition of simple integrals.

Modulation of the tissue composition of regenerative neuroma by dexamethasone and granulocyte colony-stimulating factor

Aim. To evaluate the change of the content of mesenchymal (vimentin-positive) and reparative Schwann (GFAP-positive) cells in the regenerative neuroma of the rat sciatic nerve, taking into account the activity of local homeostasis regulation (CD73 expression) under the influence of dexamethasone (Dex) and granulocyte colony-stimulating factor (GCSF). Materials and methods. Vimentin-, GFAP-, and CD73-positive cells were detected immunohistochemically in the regenerative neuroma of 168 male Wistar rats, and their presence was quantified using statistical methods. Results. The regenerative neuroma of the sciatic nerve is characterized by a stereotypical cellular composition kinetics. Dexamethasone, during the initial stage of neuroma formation (1–7 days), led to a reduction in inflammatory infiltration and accumulation of vimentin+ mesenchymal cells. It significantly accelerated the accumulation of neural GFAP+ reparative Schwann cells and suppressed the expression of CD73. The granulocyte colony-stimulating factor (1–3 days) in the regenerative neuroma resulted in a slight reduction in inflammatory infiltration and an increase in the number of blood vessels penetrating into it. Under these conditions, the speed and quantity of vimentin+ cell accumulation and CD73 expression noticeably increased, as well as the speed of GFAP+ cell accumulation. The deviations in the expression of vimentin, GFAP, and CD73 in the neuroma under the administration of the mentioned substances gradually decreased and, after 8 weeks of the experiment, did not differ significantly from the control. When combined, dexamethasone and granulocyte colony-stimulating factor potentiated each other’s effects and, in addition, led to long-term maintenance of high CD73 expression. At the same time, the most pronounced approximation of the structure of the newly formed part of the nerve to the structure of the intact nerve trunk was observed. Conclusions. The simultaneous action of Dex and GCSF during the initial stages of regenerative neuroma formation, in contrast to their individual actions, not only alters the dynamics of mesenchymal and neural cell accumulation but also modifies the newly formed part of the nerve, bringing its structure closer to the intact state. This phenomenon is accompanied by increased reactivity of neurolemocytes during the axial cylinder germination stage of neuroma regeneration.

Research on the improvement of tilt characteristics for the axial piston pump cylinder block based on the magnetic auxiliary support for distributing pair

Due to the unbalanced effect of force and torque on the axial piston pump cylinder block, a wedge angle of oil film exists between the valve plate and the cylinder block. The cylinder block tilt seriously affects the oil film and the distributing pair lubrication state, leading to boundary lubrication appears in some cases. To reduce the impact of the tilt on the cylinder block of axial piston pump, the magnetic auxiliary support (MAS) for the pair is proposed. The MAS reduces the overturning torque on the cylinder block by the auxiliary magnetic support. Then the tilt characteristics of the cylinder block are improved. In this paper, the cylinder block overturning torque equations under the support of MAS are established, and the improvement of overturning torque is analyzed. An experimental platform was constructed to measure the thickness of the oil film of the pair and test the tilt of the cylinder block. The experimental results showed that the MAS can effectively improve the tilt of the cylinder block and the performance of the axial piston pump. This method has certain reference significance for the research of axial piston pumps.

Nonlinear regimes of inertial wave attractors generated by a precessing lid: Zonal flows and Rossby waves

Fluid flow excited by inertial waves in a rotating annulus with a trapezoidal cross section is experimentally investigated. The forcing is introduced by the precession of a flat annular lid bounding the cavity. Such a setup allows to investigate interactions between inertial waves and zonal flows in the presence of equivalent topographic beta-effect, and its dynamic behavior under weak and strong forcing is experimentally studied for the first time. Due to the specific dispersion relation of inertial waves, a cavity shape supports wave attractors that appear only for retrograde lid precession. At a relatively low wave intensity, a zonal flow is generated in the vicinity of a “virtual” axial cylinder, the radius of which coincides with the radius of the focusing reflection from the conical bottom. A succession of non-linear regimes is observed as forcing increases, starting with a clearly identifiable case of triadic resonance. Further, the frequency spectrum is progressively enriched by emergence of additional discrete components, gradually reaching the state of “overheated” wave turbulence with a significant continuous background of the frequency spectrum. Finally, a strong low-frequency component develops in the frequency spectrum, and the continuous background of the spectrum decreases dramatically. The low-frequency component corresponds to azimuthally periodic structures identified as Rossby waves. In the case of strong forcing, a long-term variability of zonal-flow velocity at the timescale of tens of forcing periods is observed, which is likely a consequence of the interaction of azimuthal structures corresponding to a rich wave number set.

Ultrastructural changes of injured sciatic nerve after neurosurgical reconstruction and long-term electrostimulation in rabbits

Peripheral nerve injury is an extremely important problem during the war in Ukraine. In the overall pattern of injury, 5% of patients have peripheral nerve injuries and 1% have brachial plexus injuries. Under conditions of hostilities, this indicator increases to 70% or more. The victims are mainly young people of working age, which indicates the great medical and socio-economic significance of the problem. Materials and methods. The study was conducted on 28 rabbits Group 1 (n=7): suture of the sciatic nerve and implantation of the non-working antenna of the electrical stimulation device. Group 2 (n=7): sciatic nerve suture + implantation of an electric stimulator antenna in the same route as in group 1 and the beginning of stimulation on the 2nd day. Group 3 (n=7): sciatic nerve suture + implantation of an electric stimulator antenna in the same route as in group 1 and the beginning of stimulation 3 weeks after operation, when the first signs of regeneration occurred. Group 4 (n=7): autograft of the sciatic nerve + implantation of an electric stimulator antenna and the beginning of stimulation at a time point that will coincide with the beginning of signs of reinnervation of the effector muscle. Сontrol of regeneration was carried out in 12 weeks. The axial cylinder (AC) diameter, myelin thickness (MS) and MS/AC ratio were analyzed using electron mycroscopy. Results. It was showed a statistically significant increase of AC and MS indicators in the study group 2 relatively to comparison group 1, respectively, by 1.8 and 1.75 times. The increase of AC and MS in group 2, relatively to the comparison group and a visual decrease at the ultrastructural level of the number of destructively changed myelin sheaths (strengthening of reparative and regenerative processes) were detected. Conclusion. Therefore, long-term invasive electrostimulation of the damaged peripheral nerve has a positive effect on the regeneration of the neuromuscular complex.

Pharmacognostic studies of Trifolium fragiferum L. flora of Southern Ukraine

The work is devoted to the study of herbs of the representative genus Clover Trifolium fragiferum L. from the south Ukrainian flora. The aim of this research is to investigate the representative of Southern Ukraine flora Trifolium fragiferum L. which has a sufficient raw material base and use in folk medicine. Materials and methods. Samples were grown in the suburbs of Zaporizhzhia and harvested during full flowering (May – June). Microscopic analysis was performed with temporary preparations of leaves and stems. Plant extracts were analyzed chromatographically using an Agilent Technologies 6890 gas chromatograph with mass spectrometric detection. Results. The leaf is covered with parenchymal cells with slightly thickened membranes with anocytic stomata. The main parenchyma is composed of rounded toxoid cells. Stem rounded, covered with elongated parenchymal cells with thin membranes with almost no stomata and pubescence. Central axial cylinder is of beam type. Beams are open collateral, large. Above the phloem of the bundles is a multilayered sclerenchyma. The core is partially filled, hollow in the center. 63 compounds were found in the native extract, of which 37 were identified: coumarins, fatty acids, diterpene alcohols, oxygenated hydrocarbons of terpenoid nature, higher hydrocarbons, representatives of phytosterols, and phytosterols. After acid hydrolysis with sulfuric acid, 58 compounds were found, of which 49 were identified: coumarins, alcohols and phenols, aldehydes and ketones, compounds of diterpene nature. Conclusions. Pharmacognostic analysis of the genus Clover Trifolium fragiferum L. revealed diagnostic microscopic signs of leaves and stems. The components of the native extract are compared, and after its acid hydrolysis. Certain regularities in the distribution of classes of substances that characterized certain types of extracts were revealed: monoterpenoids, aromatic, heterocyclic compounds characterized the hydrolyzed product. Sesquiterpenes and steroid compounds are found only in the native extract of strawberry clover herb. Alcohols, aldehydes, and ketones were the majority in the hydrolyzed extract, and hydrocarbons were observed more in the native. Only 5 components were identified in both extracts: nonacosan, 2-phenoxyethanol, loliolide, dihydroactinidiolide and coumarin with significant differences in amounts.

Threading holder based on axial metal cylinder pins to reduce tap risk during reversion instant

Internal thread profiles are used widely in manufacturing processes with the aim of assembling/disassembling different components during maintenance activities from the aeronautics sector until common industrial parts. The threading process is one of the last operations carried out to obtain those components, and consequently, it is an operation of high added value. Threading is a complex operation that must carefully synchronize the rotation with the feed movements to avoid tool breakage during the instant of tapping reversion stage. In order to avoid this risk, several toolholders were developed present in the literature but deficiencies in terms of stability and productivity. Therefore, in this work, a new toolholder is proposed in which the common springs used to mitigate the lack of perfect synchronization between rotation and feed movements are replaced by elastic metal pins achieving a torsional compliance toolholder. The results show that the use of the proposed toolholder implies not only a productivity increase but also a surface integrity improvement as well as a stress reduction that the cutting tap is subjected and thus, achieving a substantial improvement in the current tapping processes. In particular, the use of the proposed toolholder implied a 75% reduction of the maximum stress achieved in the reversal instant, improving 20% tool life with an increase of 30% cutting speed. Therefore, the use of the proposed toolholder implies a substantial improvement in the current tapping processes.

On the influence of axial cylinder distortions on lubricant film and friction force of top piston ring conjunction near to TDC

ABSTRACT The purpose of this paper was to understand how axial cylinder distortions influence the tribological performance of piston ring. The current model contains the effects of axial distortions and ring conformability under mixed to hydrodynamic regimes of lubrication through computational fluid dynamics predictions. The axial cylinder profiles were modelled using series of sinusoidal waves. The effect of axial distortions on ring wear rate was determined using the Archard’s model. The ring friction and minimum lubricant film were predicted for low and high combustion pressures near to top dead centre. The study shows that, when the maximum combustion pressure rises, the different wear identities affect the operation of the ring friction much more limited, while the number of sine waves are more pronounced. Finally, it is proved that, even the increase of oil film thickness, it does not presuppose the reduction of friction when it comes to shaping the surface of the cylinder liner.

SCHWARZSCHILD SPHERE AND NASTASENKO SPINNERET

The study of black holes deepens the understanding of the structure of the foundations of the material world and the Universe, which is an urgent and important task that has not yet been fully resolved. Its solution is the main goal of this work, and the substantiation of the shape and structure of black holes on the basis of strict laws of nature is its scientific novelty. The research methods used in the work are based on deduction and induction, on the application of reliable laws of physics and the general principles of the theory of knowledge. Other methods are partially taken into account, because this work is related to scientific discoveries, the search for which is difficult to formalize. Results and its discussion. The paper puts forward a hypothesis that at the quantum level of the material world, the Schwarzschild sphere should be replaced by a spinneret of two layers of hexagonal prisms of circular space quanta, which are formed by six regular trihedral prisms of elementary space quanta with face length λG = 4.05126×10-35 m, of equal to the length waves of the gravitational field that forms them. Conclusions. It is shown that the spinnerets radius R = λG and its mass change by quantum jumps, and its internal structure consists of cylindrical layers, the radius of which increases from the first axial cylinder to the peripheral one by the quantum value λG. The spinnerets can have the properties of a black and white hole, which corresponds to the principles of Einstein's GR.

Design and Test of a Tangential-Axial Flow Picking Device for Peanut Combine Harvesting

This study presents a tangential-axial flow picking device for peanut combine harvesting. The device was designed with reference to the tangential-axial flow threshing mechanism of the grain combine harvesters. The main purpose of this study was to solve the problem of the high rate of loss and damage in the picking operation of the peanut combine harvesters in China. Through the theoretical analysis and design calculation of the key components of the peanut picking device, the structural and working parameters were determined. The orthogonal test was carried out by taking the feeding amount of the peanut plant, the picking clearance, the speed of the tangential cylinder, and the speed of the axial cylinder as the test factors. Additionally, the non-picking loss rate, entrainment loss rate, and damage rate of the peanut pods were used as the test indexes. The test results were analyzed by range analysis and analysis of variance, and the test parameters were optimized by fuzzy comprehensive evaluation method. The optimal parameter combination for the tangential-axial flow picking device was determined as follows. The feeding amount of the peanut plant was 2 kg/s, the picking clearance was 35 mm, the speed of the tangential cylinder was 360 r/min, the speed of the axial cylinder was 425 r/min. At this time, the non-picking loss rate was 0.52%, the entrainment loss rate was 0.54%, and the damage rate was 0.75%. The test results fully met the standard requirements of the peanut picking operation. This research provides a technical basis for the application of the tangential-axial flow picking device in peanut combine harvesters.

Study on Restraining Cavitation of Axial Piston Pump Based on Structure of Cylinder Block and Valve Plate Triangular Throttling Groove

Raising the rotational speed is an effective way to improve the power density of axial piston pump, but high rotational speed tends to cause plunger cavity and valve plate throttling groove cavitation. The cavitation of axial piston pump must reduce its volumetric efficiency and cause vibration and noise. In order to reduce the cavitation of axial piston pump and improve the performance of axial piston pump, the optimization of anticavitation structure parameters of cylinder block and valve plate throttling groove is studied in this paper. Firstly, according to the condition of no cavitation in the piston cavity fluid, the mathematical model of the ratio of plunger cavity diameter to axial piston pump cylinder block kidney hole hydraulic diameter is established. It is found that when the ratio is small, the cavitation degree of the piston cavity is weakened. Secondly, this paper analyzes and studies the influence of the valve plate triangular throttling groove structure parameters on the cavitation flow of the triangular throttling groove. It is found that reducing the structural parameters γ or θ can reduce the cavitation intensity of the triangular throttling groove fluid. Finally, combined with the analysis result of the ratio of piston cavity between the piston cavity diameter and the cylinder block kidney hole hydraulic diameter and the research results of the anticavitation of the valve plate triangular throttling groove, the optimized structure of anticavitation of the axial piston pump is proposed, and the simulation results show that the improved axial piston pump has better anticavitation performance.

Analysis of fatigue characteristics of dual-drive axial piston motor cylinder block

To improve the service life of axial piston motor with dual-driving, the cylinder model of axial piston motor with dual-driving is established, the cylinder force is derived and used as the boundary condition, based on the results of finite element analysis, the S-N curve of the cylinder material is modified and fatigue solution is carried out. The results show that: the main stress and strain of the cylinder block are mainly located at the cylinder block hole and the flow distribution window, the stress concentration is generated at the structural mutation, and the stress and strain are the largest; the cylinder block will be repeatedly subjected to high-pressure oil action will produce fatigue damage, fatigue damage mainly occurs at the location of higher stress.

Insights into the structure and morphogenesis of the giant basal spicule of the glass sponge Monorhaphis chuni

BackgroundA basal spicule of the hexactinellid sponge Monorhaphis chuni may reach up to 3 m in length and 10 mm in diameter, an extreme case of large spicule size. Generally, sponge spicules are of scales from micrometers to centimeters. Due to its large size many researchers have described its structure and properties and have proposed it as a model of hexactinellid spicule development. Thorough examination of new material of this basal spicule has revealed numerous inconsistencies between our observations and earlier descriptions. In this work, we present the results of detailed examinations with transmitted light and epifluorescence microscopy, SEM, solid state NMR analysis, FTIR and X-ray analysis and staining of Monorhaphis chuni basal spicules of different sizes, collected from a number of deep sea locations, to better understand its structure and function.ResultsThree morphologically/structurally different silica layers i.e. plain glassy layer (PG), tuberculate layer (TL) and annular layer (AL), and an axial cylinder (AC) characterize adult spicules. Young, immature spicules display only plain glassy silica layers which dominate the spicule volume. All three layers i.e. PG, TL and AL can substitute for each other along the surface of the spicule, but equally they are superimposed in older parts of the spicules, with AL being the most external and occurring only in the lower part of the spicules and TL being intermediate between AL and PG. The TL, which is composed of several thinner layers, is formed by a progressive folding of its surface but its microstructure is the same as in the PG layer (glassy silica). The AL differs significantly from the PG and TL in being granular and porous in structure. The TL was found to display positive structures (tubercles), not depressions, as earlier suggested. The apparent perforated and non-perforated bands of the AL are an optical artefact. The new layer type that we called the Ripple Mark Layer (RML) was noted, as well as narrow spikes on the AL ridges, both structures not reported earlier. The interface of the TL and AL, where tubercles fit into depressions of the lower surface of the AL, represent tenon and mortise or dovetail joints, making the spicules more stiff/strong and thus less prone to breaking in the lower part. Early stages of the spicule growth are bidirectional, later growth is unidirectional toward the spicule apex. Growth in thickness proceeds by adding new layers. The spicules are composed of well condensed silica, but the outermost AL is characterized by slightly more condensed silica with less water than the rest. Organics permeating the silica are homogeneous and proteinaceous. The external organic net (most probably collagen) enveloping the basal spicule is a structural element that bounds the sponge body together with the spicule, rather than controlling tubercle formation. Growth of various layers may proceed simultaneously in different locations along the spicule and it is sclerosyncytium that controls formation of silica layers. The growth in spicule length is controlled by extension of the top of the axial filament that is not enclosed by silica and is not involved in further silica deposition. No structures that can be related to sclerocytes (as known in Demospongiae) in Monorhaphis were discovered during this study.ConclusionsOur studies resulted in a new insight into the structure and growth of the basal Monorhaphis spicules that contradicts earlier results, and permitted us to propose a new model of this spicule’s formation. Due to its unique structure, associated with its function, the basal spicule of Monorhaphis chuni cannot serve as a general model of growth for all hexactinellid spicules.

A Nitric Oxide–Modulated Variable-Order Fractional Maxwell Viscoelastic Model of Cerebral Vascular Walls

It is well known that the mechanical behavior of arterial walls plays an important role in the pathogenesis of vascular diseases. Most studies existing in the literature focus on the mechanical interactions between the blood flow and wall’s deformations. However, in the brain, the smaller vessels experience not only oscillatory forces due to the pulsatile blood flow but also structural and morphological changes controlled by the surrounding brain cells. In this study, the mechanical deformation of the cerebral arterial wall caused by the pulsatile blood flow and the dynamics of the neuronal nitric oxide (NO) is investigated. NO is a small diffusive gaseous molecule produced by the endothelial cells and neurons, which is involved in the regulation of cerebral blood flow and pressure. The cerebral vessel is assumed to be a hollow axial symmetric cylinder whose wall thickness is much smaller than the cylinder’s radius and longitudinal length is much less than the propagating wavelength. The wall is an isotropic, homogeneous linear viscoelastic material described by an NO-modulated variable-order fractional Maxwell model. A fractional telegraph equation is obtained for the axial component of the displacement. Patterns of wall’s deformation are investigated through numerical simulations. The results suggest that a significantly decreased inactivation of the neuronal NO may cause a reduction in the shear stress at the blood-vessel interface, which could lead to a decrease in the production of shear-induced endothelial NO and neurovascular disease.

Significance of selenium supplementation in root- shoot reactions under manganese stress in wheat seedlings \u2013 biochemical and cytological studies

PurposeAgronomic practices are one of the reasons for the increasing accumulation of elements in the soil, including manganese (Mn). Our previous studies have shown that selenium (Se) ions can reduce the toxic actions of metal stress. Those, we studied the effects of Mn—treated as a stressor and Se – as a potential defense in plants.MethodsMn ions (10 mM) or/and Se (15 μM) were added into hydroponic nutrients of two wheat cultivares. The evaluation of the stress-generating and protective actions were analyzed by biochemical methods and microscopic observations in leaves and roots. Moreover the level of DNA methylation for these tissues was determined.ResultsMn application caused an increase of lipid peroxidation and hydrogen peroxide content in both leaves and roots and was accompanied with a greater absorption of this element by the roots. For other elements (K, Fe, S, P), with the exception of Ca, the reduced their uptake was registered, especially in roots. For roots, Mn stimulated greater, microscopically observed, desorganization in cell structure as compared to leaves, which was accompanied by a quantitative increase in 5-methylcytosine (5-metC) in root meristem. Se application diminished the effects of Mn-stress.ConclusionsThese studies is the first in which indicated that global 5-metC level in roots enhancing from dividing meristematic cells to elongating cells of the axial cylinder and cortex. It was suggested that the rise in Ca level can lead to modification of root cells differentiations what may be one of the steps in defense mechanisms.

Study on the Distribution Pattern of Threshed Mixture by Drum-Shape Bar-Tooth Longitudinal Axial Flow Threshing and Separating Device

To determine the distribution pattern of the threshing and separating device, the simulation experiment on the distribution pattern of our self-designed drum-shape bar-tooth longitudinal axial flow threshing and separating device was carried out with the help of the EDEM software, by which the axial and radial distribution curve of the threshed mixture along the cylinder was acquired. The three-dimensional distribution of the mass of the threshed mixture was drawn by using the Matlab software, and the bench test was carried out on the self-built small-scale longitudinal axial flow threshing cylinder performance test platform, which was consistent with the simulation conditions. The results showed that the axial and radial distribution of the threshed mixture was uneven, and the axial distribution of the threshed mixture decreased gradually, which was mainly distributed in the first third section of the cylinder. The distribution of the threshed mixture along the radial area of the cylinder was gradually decreasing at first and then increasing, i.e., the total mass of the threshed mixture on the left and right sides was higher than that of the middle area, which was basically consistent with the simulation results. The research can provide reference for the optimization of structural parameters of threshing and separating device and cleaning system.

Morphological manifestations of experimental paclitaxel-induced sciatic neuropathy under correction of 2-ethyl-6-methyl-3-hydroxypyridine succinate

Paclitaxel is an effective chemotherapeutic agent for many cancers, but it has a number of limiting side effects that not only significantly reduce the quality of life of patients, but also limit their further treatment. Peripheral neuropathy is one of these, but there are currently no proven effective druHS for the prevention or treatment of paclitaxel-induced neuropathic pain (PINP) in particular, or chemotherapy-induced peripheral neuropathy (CIPN) in general. 2-ethyl-6-methyl-3-hydroxypyridine succinate (HS) is a derivative of succinic acid with neuroprotective, antihypoxic, membrane-protective, nootropic, sedative effects.&#x0D; The aim of the study was to study the effect of the neuroprotective agent HS on the pathomorphogenesis of the sciatic nerves under conditions of paclitaxel-induced peripheral neuropathy in the experiment.&#x0D; Materials and methods. The experiment was carried out on 80 white rats, which were injected intraperitoneally with paclitaxel (Actavis, Romania), previously dissolved in isotonic saline at a dose of 2 mg / kg of body weight four times every other day until a total dose of 8 mg / kg was reached. Then forty of these animals were injected intraperitoneally with 2-ethyl-6-methyl-3-hydroxypyridine succinate at a dose of 10 mg / kg (the remaining 40 rats received intraperitoneal water for injection). Morphological studies were carried out on the first, seventh, fifteenth, twenty-eighth, sixtieth, ninetieth and one hundred and twentieth days after the last injection of the drug. We investigated the pharmacological potential of HS in the prevention and treatment of CIPN at the level of sciatic nerve (SN) morphology.&#x0D; Results. The maximum value of the average profile area of myelinated nerve fibers with the use of HS is significantly lower than with uncorrected flow, and is (78.12±2.24) μm2 compared to (94.04±1.03) μm2 (p &lt;0.001). The introduction of HS provides a stable content of the value of the ratio of the areas of the axial cylinder and the fiber within 0.39±0.01 (first day) - 0.44±0.01 (ninetieth day), and a rapid recovery of the indicator value to normal values during the final 30 days of the experiment. the maximum value of the index of the profile area of the myelin sheath with the introduction of HS is 1.4 times less than with an uncorrected flow, and is, respectively, (49.01±1.59) μm2 and (69.77±1.87) μm2 (p &lt;0.001). HS provides a more intensive restoration of the indicator of the area of the myelin sheath during the 90th - 120th day of the experiment.&#x0D; Conclusions. Our results allow us to conclude that the introduction of HS creates a protective effect against paclitaxel-induced peripheral neuropathy (PIPN) by acting on both the axial cylinder and the myelin sheath of the heart failure. Due to the known pathophysiological mechanisms of the development of neuropathy, this method can be a promising therapeutic agent for the prevention and treatment of PIPN

MORPHOLOGICAL MANIFESTATIONS OF EXPERIMENTAL PACLITAXEL-INDUCED SICK NERVE NEUROPATHY UNDER CORRECTION OF 2-ETHYL-6-METHYLIDE-3-HYCYDYR-3-HYDYCIDE-3

Paclitaxel is an effective chemotherapeutic agent for many cancers, but has a number of limiting side effects that not only significantly reduce the quality of life of patients, but also limit their further treatment. Peripheral neuropathy is one of these, but as of today, there are no proven effective drugs for the prevention or treatment of paclitaxel-induced neuropathic pain (IDP) in particular, or peripheral chemotherapy-induced neuropathy (PIH) in general. 2-ethyl-6-methyl-3-hydroxypyridine succinate (HS) is a derivative of succinic acid with neuroprotective, antihypoxic, membrane-protective, nootropic, sedative action. The experiment was performed on 80 white rats injected intraperitoneally with paclitaxel (Actavis, Romania), pre-dissolved in isotonic saline at a dose of 2 mg / kg body weight four times a day until a total dose of 8 mg / kg. Forty of these animals were then injected intraperitoneally with 2-ethyl-6-methyl-3-hydroxypyridine succinate at a dose of 10 mg / kg (the other 40 rats received intraperitoneal water for injection). Morphological studies were performed on the 1st, 7th, 15th, 28th, 60th, 90th and 120th days after the last administration of the drug. We investigated the pharmacological potential of HS in the prevention and treatment of PNH at the level of the sciatic nerve (CH). Our results allow us to conclude that the introduction of HS creates a protective effect against paclitaxel-induced peripheral neuropathy (PIPN) by affecting both the axial cylinder and the myelin sheath of HF. Due to the known pathophysiological mechanisms of neuropathy, this method can be a promising therapeutic tool for the prevention and treatment of PIPN.